Evaporator having folded baffles

ABSTRACT

A evaporator provides an evaporator that includes an evaporator core, an evaporator tank attached to the evaporator core, and at least one single-piece and folded baffle having raised surfaces incorporated into the evaporator tank. The baffle has opposed sides having a pair of opposed raised surfaces. The baffle further includes a top edge and a side edge. The pair of opposed raised surfaces is provided adjacent one of the edges and includes two pairs of opposed raised surfaces. The raised surface can be a flat-sided ramp, a curve-sided ramp, or a dimple.

TECHNICAL FIELD

The disclosed inventive concept relates to vehicle air conditioningsystems and particularly to the evaporator of such systems. Moreparticularly, the disclosed inventive concept relates to a baffle for anevaporator tank wherein the baffle is a cladded and folded plate havingelevated areas, the baffle being brazed or otherwise attached to theevaporator tank.

BACKGROUND OF THE INVENTION

Most vehicles today include air conditioning systems to provide forimproved occupant comfort. While being first introduced in theautomotive world several decades ago, air conditioning systems havechanged little. Thus the fundamental parts of the modern vehicle's airconditioning system are known and understood. These parts include thecompressor, the condenser, the evaporator, the thermal expansion valve,and the drier or accumulator. In many ways the compressor is the heartof the vehicle's air conditioning system. The compressor pressurizes hotgaseous refrigerant and forces it on to the condenser. The condenser,which is like a small radiator, cools the hot gases received from thecompressor. As these gases cool, they become liquid in the condenser.

Liquid refrigerant leaves the condenser under high pressure and entersthe drier or accumulator. The drier catches any liquid water that mayinadvertently have entered the system. The liquid refrigerant, oncecleared of any water, flows to the expansion valve which functions toremove pressure from the liquid refrigerant and literally allows it toexpand. This reduction of pressure allows the liquid refrigerant toreturn to the vapor stage in the evaporator, the refrigerant's nextstop.

The evaporator is also similar in shape and function to a smallradiator. Typically the evaporator is fitted inside of the vehicle'spassenger compartment in or around the instrument panel. Thestill-liquid refrigerant enters the evaporator under low pressure fromthe expansion valve. The liquid refrigerant vaporizes while absorbingheat from inside the car. Cold air is circulated within the passengercompartment by a fan that pushes air across the fins of the evaporator.Low pressure refrigerant, now in gaseous form, exits the evaporator andreturns to the compressor where the cycle is repeated.

Evaporators are typically manufactured from aluminum and usually includean upper tank, a lower tank and a series of refrigerant-containing tubesfitted there between. Baffles are located within the tanks to regulatethe flow of liquid refrigerant. The baffles are usually brazed to theinner wall of the tank. However, known technology makes positioning thebaffles during the brazing process challenging and frequently results inthe baffles being out of alignment prior to the brazing process.

Accordingly, an improvement in evaporator design and assembly isrequired to overcome the challenges faced by the prior art.

SUMMARY OF THE INVENTION

The disclosed inventive concept overcomes the problems associated withknown evaporators by providing an arrangement in which the baffles arefixed in position prior to brazing to provide an accurate andfluid-tight seal without error and with minimum production time. Thedisclosed inventive concept provides an evaporator that includes anevaporator core, an evaporator tank attached to the evaporator core, andat least one single-piece and folded baffle having raised surfacesincorporated into the evaporator tank.

The evaporator tank includes an interior wall. The raised surface has awall-contacting portion that is in contact with the interior wall. Moreparticularly, the baffle has two opposed sides. Each of the opposed sidehas a raised surface defined by a pair of opposed raised surfaces. Thebaffle further includes a top edge and a side edge. The pair of opposedraised surfaces is provided adjacent one of the edges and includes twopairs of opposed raised surfaces. One of the two pairs of opposedsurfaces is provided adjacent the top edge of the baffle and the otherof the two pairs of opposed surfaces is provided adjacent the side edgeof the baffle. The raised surface is selected from the group consistingof a flat-sided ramp, a curve-sided ramp, and a dimple.

The above advantages and other advantages and features will be readilyapparent from the following detailed description of the preferredembodiments when taken in connection with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

For a more complete understanding of this invention, reference shouldnow be made to the embodiments illustrated in greater detail in theaccompanying drawings and described below by way of examples of theinvention wherein:

FIG. 1 is an isometric view of a evaporator according to the disclosedinventive concept;

FIG. 2 is an exploded view of the upper portion of the evaporator ofFIG. 1 showing the upper tank in spaced apart relation to the coolingfins and the end plate assemblies and baffles also spaced apart from theupper tank portions;

FIG. 3 is a perspective view of a baffle according to the disclosedinventive concept illustrating the baffle being folded from a singlesheet of material;

FIG. 4 is a perspective view of a baffle according to a first embodimentof the disclosed inventive concept;

FIG. 5 is an end view of the baffle of FIG. 4;

FIG. 6 is a perspective view of a baffle according to a secondembodiment of the disclosed inventive concept;

FIG. 7 is an end view of the baffle of FIG. 6;

FIG. 8 is a perspective view of a baffle according to a third embodimentof the disclosed inventive concept;

FIG. 9 is an end view of the baffle of FIG. 8;

FIG. 10 is a perspective view of a portion of upper tank portions shownin cutaway and illustrating baffles according to the disclosed inventiveconcept;

FIG. 11 is a view taken along line 11 of FIG. 10;

FIG. 12 is a top plan view of a portion of upper tank portions shown incutaway and illustrating baffles according to the disclosed inventiveconcept;

FIG. 13 is a view taken along line 13 of FIG. 12; and

FIG. 14 is an end view of a single-layer baffle according to analternative embodiment of the disclosed inventive concept.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

In the following figures, the same reference numerals will be used torefer to the same components. In the following description, variousoperating parameters and components are described for differentconstructed embodiments. These specific parameters and components areincluded as examples and are not meant to be limiting.

The evaporator for use with an air conditioning system for a vehicleaccording to the disclosed inventive concept is illustrated in itsvarious embodiments in FIGS. 1 through 13. However, it is to beunderstood that the illustrated embodiments are suggestive and are notintended as being limiting.

The evaporator of the disclosed inventive concept is illustrated in FIG.1 while the baffles and end plates are illustrated in FIG. 2. Theevaporator of the disclosed inventive concept is a multi-pass evaporatorhaving a thickness range of between about 25 mm and 80 mm. Variousembodiments of the baffles are shown in FIGS. 3 through 9. FIGS. 10through 13 illustrate the baffles in place in the tank portions.Regardless of the embodiment, the evaporator of the disclosed inventiveconcept overcomes challenges and limitations associated with theconstruction of current evaporators.

Referring to FIG. 1, an evaporator, generally illustrated as 10, isshown. The overall configuration of the evaporator 10 as illustrated isintended as being suggestive and not limiting.

The evaporator 10 includes an upper tank assembly 12 and a lower tankassembly 14. The upper tank assembly 12 and the lower tank assembly 14are typically made of a metal, although other materials includingpolymerized materials may be used alone or in combination. A lowerpressure, liquid refrigerant input 16 is provided as is a lowerpressure, gas refrigerant output 18. The liquid refrigerant input 16 isconnected to liquid input upper tank portion 20. The gas refrigerantoutput 18 is connected to a gas output upper tank portion 24. A seriesof refrigerant-containing tubes 26 fluidly connect the upper tankassembly 12 and the lower tank assembly 14.

Referring to FIG. 2, an exploded view of the upper portion of theevaporator 10 is illustrated in spaced apart relation to therefrigerant-containing tubes 26, a pair of baffles 27, and a pair of endplate assemblies 28. One of the end plate assemblies 28 is shownseparated into its two portions, an inner end plate 30 having an inletrefrigerant input passageway 31 and an outlet refrigerant outputpassageway 32, and an outer end plate 33 having an inlet refrigerantinput port 34 (connected to the liquid refrigerant input 16) and anoutlet refrigerant output port 36 (connected to the gas refrigerantoutput 18). The illustrated shapes of the baffles 27, the inner endplate 30 and the outer end plate 33 may be altered from the illustratedshapes without varying the scope of the present invention.

FIGS. 3 through 9 illustrate various embodiments of the baffle of thedisclosed inventive concept. A single type of baffle may be used in asingle tank or different embodiments of the baffle may be used.

In FIG. 3, a perspective view of the baffle 27 is illustrated. Thebaffle 27 is preferably stamped from a single piece of cladded sheetaluminum and is then folded as illustrated to form the two-layer baffleof the disclosed inventive concept. The baffle 27 includes a firstbaffle half-portion 38 and a second baffle half-portion 40.

The folding of the baffle 27 provides spring back that helps to retainthe baffle 27 inside the evaporator tank. This feature results in arobust brazing process to prevent any internal refrigerant leaks.

In addition to folding as a method of retaining the baffle 27 in itspre-brazed position within the tank, the baffle 27 is also provided withraised areas that contact the inner wall of the tank. In this way, thebaffle 27 is held in place during the brazing process. In addition toFIG. 3, this arrangement according to a first embodiment of thedisclosed inventive concept is also illustrated in FIGS. 4 and 5.

A pair of opposed upper ramped raised areas 42 and 42′ are provided tocontact the inside top wall of the tank while a pair of opposed lowerramped raised areas 44 and 44′ are provided to contact the inside sidewall of the tank. In combination with the springing action of the foldedbaffle 27, the ramped raised areas 42, 42′, 44 and 44′ retain the baffle27 in its proper aligned position to allow correct brazing of the baffle27 in place within the tank.

FIGS. 6 and 7 illustrate raised areas according to an alternateembodiment of the disclosed inventive concept. Particularly, a baffle 50is showing having a first baffle half-portion 52 and a second bafflehalf-portion 54. A pair of opposed, upper semi-circular raised areas 56and 56′ and a pair of opposed, lower semi-circular raised areas 58 and58′ are formed on the baffle 50. In combination with the springingaction of the folded baffle 50, the semi-circular raised areas 56, 56′,58 and 58′ retain the baffle 50 in its proper aligned position to allowcorrect brazing of the baffle 50 in place within the tank.

FIGS. 8 and 9 illustrate raised areas according to a third embodiment ofthe disclosed inventive concept. Particularly, a baffle 60 is showinghaving a first baffle half-portion 62 and a second baffle half-portion64. A pair of opposed, upper dimpled raised areas 66 and 66′ and a pairof opposed, lower dimpled raised areas 68 and 68′are formed on thebaffle 60. In combination with the springing action of the folded baffle60, the dimpled raised areas 66, 66′, 68 and 68′ retain the baffle 60 inits proper aligned position to allow correct brazing of the baffle 60 inplace within the tank.

Beyond the configurations of the raised areas illustrated in FIGS. 3through 9, other configurations are possible, provided contact is madebetween the raised area and the upper or side wall of the interior ofthe tank. Accordingly, the embodiments shown are intended as beingsuggestive and not limiting.

FIGS. 10 through 13 illustrate adjacent baffles 27 in position relativeto the upper tank in various views. Particularly, is a perspective viewof a portion of an evaporator 10 shown in cutaway and illustratingside-by-side baffles 27 while FIG. 11 is a view taken along line 11 ofFIG. 10. The ramped raised areas 42 and 42′ are illustrated as being incontact with an inner wall 70 of the gas output upper tank portion 24.The other raised areas (not shown) are also in similar contact.

FIG. 12 is a top plan view of a portion of an evaporator 10 shown incutaway and illustrating more particularly the side-by-side relationshipof the baffles 27 according to the disclosed inventive concept. FIG. 13is a more detailed view of the side-by-side arrangement of the baffles27 taken along line 13 of FIG. 12. Once the baffles 27 are positionedinside of the tank portions 20 and 24, the baffles 27 are brazed inposition, thus permanently securing the baffles 27 inside the tankportions 20 and 24.

FIG. 14 illustrates an alternative approach to a baffle according to thedisclosed inventive concept. As shown in this figure, a flat platebaffle 42 is formed from a non-folded, single layer of material. Theflat plate baffle 42 includes a first outer side 44 and a second outerside 46. Formed on the first outer side 44 is a pair of raised areas 48and 48′ and formed on the second outer side 46 is a pair of raised areas50 and 50′. Because the flat plate baffle 42 is formed from a singlelayer, the positions of the raised areas 48 and 48′ are offset withrespect to the positions of the raised areas 50 and 50′ due tomanufacturing constraints. It is to be understood that while the raisedareas 48, 48′, 50 and 50′ are dimples, other configurations such as theramps and semi-circles discussed above could be incorporated as well.

The disclosed inventive concept shown in the accompanying figures anddescribed above effectively overcomes the problems known to beassociated with known evaporators. By providing a system and method forproperly aligning the baffles relative to the tank portions, properbrazing can be achieved.

While the preferred embodiments of the disclosed inventive concept havebeen discussed are shown in the accompanying drawings and are set forthin the associated description, one skilled in the art will readilyrecognize from such discussion, and from the accompanying drawings andclaims that various changes, modifications and variations can be madetherein without departing from the true spirit and fair scope of theinvention as defined by the following claims.

What is claimed is:
 1. An evaporator for use with a refrigerant, theevaporator comprising: an evaporator core; an evaporator tank attachedto said core; a baffle incorporated into said evaporator tank, saidbaffle comprising a single folded sheet and having at least one raisedsurface.
 2. The evaporator for use with a refrigerant of claim 1,wherein said evaporator tank includes an interior wall and wherein saidraise surface has a wall-contacting portion, said wall-contactingportion being in contact with said interior wall.
 3. The evaporator foruse with a refrigerant of claim 1, wherein said baffle has two opposedsides and wherein each of said opposed side has a raised surface definedby a pair of opposed raised surfaces.
 4. The evaporator for use with arefrigerant of claim 3, wherein said baffle has a top edge and a sideedge, said pair of opposed raised surfaces being provided adjacent oneof said edges.
 5. The evaporator for use with a refrigerant of claim 4,including two pairs of opposed raised surfaces.
 6. The evaporator foruse with a refrigerant of claim 5, wherein one of said two pairs ofopposed surfaces is provided adjacent said top edge of said baffle andthe other of said two pairs of opposed surfaces is provided adjacentsaid side edge of said baffle.
 7. The evaporator for use with arefrigerant of claim 1, wherein said raised surface is selected from thegroup consisting of a flat-sided ramp, a curve-sided ramp, and a dimple.8. A baffle for use in an evaporator tank, the baffle comprising: asingle folded plate; a first sided; a second side; a pair of opposedraised surfaces, one of said raise surfaces being formed on said firstouter side and the other of said pair of surfaces being formed on saidsecond outer side.
 9. The baffle for use in an evaporator tank of claim8, wherein said raise surface has a wall-contacting portion.
 10. Thebaffle for use in an evaporator tank of claim 8, wherein said baffle hastwo opposed sides and wherein each of said opposed side has a raisedsurface defined by a pair of opposed raised surfaces.
 11. The baffle foruse in an evaporator tank of claim 10, wherein said baffle has a topedge and a side edge, said pair of opposed raised surfaces beingprovided adjacent one of said edges.
 12. The baffle for use in anevaporator tank of claim 11, including two pairs of opposed raisedsurfaces.
 13. The baffle for use in an evaporator tank of claim 12,wherein one of said two pairs of opposed surfaces is provided adjacentsaid top edge of said baffle and the other of said two pairs of opposedsurfaces is provided adjacent said side edge of said baffle.
 14. Thebaffle for use in an evaporator tank of claim 8, wherein said raisedsurface is selected from the group consisting of a flat-sided ramp, acurve-sided ramp, and a dimple.
 15. An evaporator for use with arefrigerant, the evaporator comprising: an evaporator core; anevaporator tank attached to said core, said tank having an inner wall; abaffle incorporated into said tank, said baffle having opposed outerwalls, each of said walls having a raise surface, each raised surfacehaving a core inner wall-contacting surface positioned against saidinner wall of said tank.
 16. The evaporator for use with a refrigerantof claim 15, wherein said baffle is a single piece of folded metal. 17.The evaporator for use with a refrigerant of claim 15, wherein saidraised surface is selected from the group consisting of a flat-sidedramp, a curve-sided ramp, and a dimple.
 18. An evaporator for use with arefrigerant, the evaporator comprising: a liquid-passing grill; aliquid-holding tank fluidly attached to said grill, said tank having atop wall, a bottom wall, and a pair of spaced-apart side walls; aone-piece, folded baffle having an upper portion, a bottom portion, apair of spaced-apart side portions, a first outer wall and a secondouter wall, said top portion being attached to said top wall, saidbottom portion being attached to said bottom wall, and said sideportions being attached to said side walls, said baffle furtherincluding a surface elevated from at least one of said outer walls, saidsurface having an edge, said edge being attached to one of said walls ofsaid tank.
 19. The evaporator for use with a refrigerant according toclaim 18 in which said elevated surface is selected from the groupconsisting of ramps, semi-circles and dimples.
 20. The evaporator foruse with a refrigerant according to claim 18 in which said baffle iscladded.